What is Reorganization (Reorg)?
A reorg happens when nodes switch to a longer (more work) chain than the one they previously followed. Short reorgs of one or two blocks are normal; deep reorgs are rare and would indicate either a serious problem or a large-scale attack.
Why Reorganization (Reorg) matters
Understanding Reorganization (Reorg) is part of building a solid mental model of how Bitcoin, blockchain and Web3 systems actually work. Concepts in the Blockchain category sit at the foundation of the broader stack — get them right and the rest is far easier.
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Related terms
- Fork — A divergence in the blockchain or its rules.
- Consensus Mechanism — The rules a network uses to agree on the canonical chain.
- Confirmation — A block built on top of the block containing a transaction.
More blockchain terms
- Block — A bundle of transactions added to the blockchain.
- Blockchain — A chained, append-only ledger of blocks.
- Node — A computer participating in the blockchain network.
- Proof of Stake — A consensus mechanism where validators stake capital instead of burning energy.
- Transaction — A signed instruction that updates the blockchain state.
- Block Time — Average interval between consecutive blocks.
- Genesis Block — The first block in a blockchain.
Keep exploring
Continue with the full blockchain glossary — 136 terms in total — or read the developer blog and FAQ for deeper context.